Pachyrhizus, also known as yarn bean, Pachyrrhyizus erosus, sweet potato, Rosa fruits, and ground radish, is a cultured species of Leguminous pachyrhizus that can form root tubers. It is an annual or perennial herbaceous twining vine, and it is native to tropical America, There are many cultivated species in Sichuan, Chongqing, Hubei and Hunan, Guangdong and Guangxi and Taiwan in China.
The edible part of Pachyrhizus is the large root tubers, which is rich in starch. According to the determination, each kilogram of root tuber contains 810˜880 g of water, 76-119 g of carbohydrates and some minerals and vitamins. Its meat is white, tender, crisp, sweet, juicy, which can be eaten without cooking, or can be cooked, or processed into powder, having the cool and refreshing effect. Pachyrhizus has superior flavor and considerable medicinal value, and it has the efficacy of clearing heat and nourishing Yin and promoting secretion of saliva or body fluid, Pachyrhizus can be eaten naturally or juiced to drink, which can treat the fever, thirst, sore throat caused by cold; and the dysphoria with smothery sensation, hectic fever, night sweats, dysphoria hot, insomnia and women's menopausal symptoms caused by deficiency of yin and blood. At present, there are very fewer studies on the edible methods of Pachyrhizus, and almost no one develops it. The existing method of Pachyrhizus products is very simple, with less flavor. The edible part of Pachyrhizus is its root tubers in a spindle-shape or flat round shape, and its peel is pale yellow an d the flesh is white. Pachyrhizus is juicy, sweet, with unique aroma and flavors, and its juice yield rate is 70% to 75%. The tuber fruits are rich in water, carbohydrates and minerals, etc., which are the good sources of potassium, calcium, minerals and carbohydrates. It has the efficacy of producing saliva and slaking thirst, called “underground pear.” However, its seeds, stems and leaves contain rotenone (C23H2206), which is highly toxic to humans and animals, and it can be made into DDVP and other pesticides.
CN103039902A disclosed high fructose syrup of Pachyrhizus made of the raw material Pachyrhizus. Its preparation contains the following steps: (1) pretreatment of raw materials: washing the Pachyrhizus clean and removing the peel, juicing it by a juicer, filtering to collect the Pachyrhizus juice; (2) Pulp mixing: adjusting the pH value of the Pachyrhizus juice obtained in step (1) with phosphoric acid to 6.0-7.0, adding amylase with the amount of 0.2-0.4% Pachyrhizus juice weight, and stirring well; (3) high temperature liquefaction: jetting the Pachyrhizus juice for liquefaction at 100˜120° C., and the liquefaction time is controlled within 30-50 min, to prepare the liquefied solution; (4) saccharification: cooling down the liquid obtained in step (3) to 30˜40° C., adjusting the pH value with hydrochloric acid to 4.5˜5.5, and saccharifying by adding glucoamylase with the amount, of glucoamylase equal to 0.1˜0.2% of the weight of liquid. The saccharification time is controlled within 42˜56 hours; then heating to 85˜95° C. for enzyme inactivation, to obtain the saccharification liquid, (5) heterogeneous conversion: adding sodium phosphate solution to the saccharification liquid obtained in step (4) to adjust pH value to 5.7˜6.7, then adding glucose isomerase for conversion, with the amount of glucose isomerase to be 0.1 to 0.2% of the weight of saccharified liquid; the conversion temperature controlled at 45˜55° C. and the conversion time at 20˜30 hours, and then heating to 85˜95° C., to inactivate the glucose isomerase to obtain heterogeneous sugar liquid; (6) concentration: concentrating the heterogeneous sugar liquid obtained in step (5) with a rotary evaporator, with the concentration temperature controlled at 50˜60° C., and concentrating until the solids content to be 60˜70%; (7) packaging: cooling down the concentrates obtained in step (6) to 30˜40° C., and packaging to obtain the finished products.
CN104323380A disclosed a method for producing Pachyrhizus beverage; peeingl off the fruit skin of 50 kg Pachyrhizus by hands, washing once with water; cutting the Pachyrhizus into fine grains, putting into a deep pot and adding water to soak for 10 min, then heating to boil and maintaining for 20 min, and then sucking the liquid to a stainless steel container through a water pump to precipitate for 1 day, and then filtering once through a filter screen; weighing 2 tons of liquid and pouring to a mixer, then adding 15 kg of citric acid, 20 kg of white sugar, 2 g of flavor and 10 g of sodium benzoate, stirring for 15 min using a mixer, and then delivering to the fine filter to filter through a sanitary pump, then entering the liquid storage tank, transporting to a plastic bottle with a sanitary pump for automatic filling, and then covering and packaging them.